The Relationships Between Cortical Activity while Observing Images Featuring Different Degrees of Ambiguity and Ambiguity Tolerance.

We performed a fMRI study during which 18 healthy subjects passively viewed abstract images and tried to name them. The images were geometric primitives, impossible images (Penrose images), and ambiguous images (Rorschach inkblots). Activation and deactivation areas were revealed for each task. The results of psychological assessment of ambiguity tolerance according to MSTAT-I inventory were used as regressors. Deactivation of the precuneus (Brodmann area 7) and neighboring structures (especially when observing geometric primitives and inventing names for them) and in the fronto-temporal areas was associated with high ambiguity tolerance. Similar links were observed for both activation and deactivation (depending on the certain contrast) of the occipito-cerebellar area.